title: Molecular genetic gene-environment studies using candidate genes in schizophrenia: a systematic review.
abstract: The relatively high heritability of schizophrenia suggests that genetic factors play an important role in the etiology of the disorder. On the other hand, a number of environmental factors significantly influence its incidence. As few direct genetic effects have been demonstrated, and there is considerable inter-individual heterogeneity in the response to the known environmental factors, interactions between genetic and environmental factors may be important in determining whether an individual develops the disorder. To date, a considerable number of studies of gene-environment interactions (G×E) in schizophrenia have employed a hypothesis-based molecular genetic approach using candidate genes, which have led to a range of different findings. This systematic review aims to summarize the results from molecular genetic candidate studies and to review challenges and opportunities of this approach in psychosis research. Finally, we discuss the potential of future prospects, such as new studies that combine hypothesis-based molecular genetic candidate approaches with agnostic genome-wide association studies in determining schizophrenia risk.
authors.affiliation: Department of Psychosis Studies, Institute of Psychiatry, King's College London, United Kingdom. Electronic address: gemma.modinos@kcl.ac.uk.
authors.forename: Gemma
authors.initials: G
authors.lastname: Modinos
authors.forename: Conrad
authors.initials: C
authors.lastname: Iyegbe
authors.forename: Diana
authors.initials: D
authors.lastname: Prata
authors.forename: Margarita
authors.initials: M
authors.lastname: Rivera
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Kempton
authors.forename: Lucia R
authors.initials: LR
authors.lastname: Valmaggia
authors.forename: Pak C
authors.initials: PC
authors.lastname: Sham
authors.forename: Jim
authors.initials: J
authors.lastname: van Os
authors.forename: Philip
authors.initials: P
authors.lastname: McGuire
mesh_terms: D004777:Environment; D059647:Gene-Environment Interaction; D020022:Genetic Predisposition to Disease; D055106:Genome-Wide Association Study; D006801:Humans; D012559:Schizophrenia / Q000235:genetics*
keywords: Environment; Genetics; Gene–environment interaction; Psychosis; Schizophrenia